This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Primary torsion dystonia (PTD) is a chronic movement disorder manifesting clinically as focal or generalized sustained muscle contractions, postures, and/or involuntary movements. Genetic forms of PTD (e.g., DYT1 and DYT6) typically begin in childhood or adolescence and are often generalized. By contrast, sporadic PTD is more common, begins in adulthood, and is often focal or segmental in distribution. In previous studies, we have identified a consistent pattern of abnormal metabolic activity in PTD. We have also described microstructural white matter abnormalities in patients with inherited forms of PTD. In the proposed study, we will determine if similar structure/function abnormalities underlie the more common sporadic forms of PTD and whether these changes constitute useful biomarkers of the disorder.